acetaldehyde - any fixes?

I have a Kolsch that I think is showing signs of acetaldehyde. To me it comes off as more citrusy but I could see it being green apple. I thought that I pitched an adequate healthy amount of WY2565 but it was pretty sluggish from what I remember.

I packaged 3 bottles with priming sugar for a comp. Is there any chance that refermentation in the bottle for carb might help with the acetaldehyde or am I just screwed? I assume it will just stick around in the keg…

If you’ve already racked your beer off your yeast, it’s likely too late for it to be reabsorbed by the yeast.  Citrusy sounds more like hops to me, but could be perceived differently by you.  Without being able to smell or taste your beer I can’t make a reasonable guess.

Thanks. I definitely perceive it as a late hop addition but there is only one FWH addition of mittelfruh/magnum so I don’t think that would be it.

So it can’t be reabsorbed by yeast left in suspension when carbonating in regards to bottles?

Well, let’s put it this way, one possible cause of it is being taken off the yeast cake too soon.  It can be because of it being young…  But once off the yeast cake I don’t know if there will be enough in suspension to fix the problem.

Cool. Thanks for your help.

Based on your description, I’m not sure it is acetaldehyde.

Great thanks. haha…

I’ve used that yeast once for a Kolsch and I remember getting a hint of pear in the flavor…From Wyeast: This strain is a classic, true top cropping yeast strain from a traditional brewery in Cologne, Germany. Beers will exhibit some of the fruity character of an ale

Can’t help you solve a problem you may not have…

Definitely. That statement is a little more direct…

Apple is commonly an ester, especially ethyl hexanoate/ethyl caproate.  This is responsible for the apple note that many mistakenly identify as acetaldehyde in Budweiser, which actually has one of the lowest measured acetaldehyde levels in any beer.  (Nonetheless, it’s why I don’t like Bud!)

This is true.

The myth that bud has detectable acetaldehyde still lives on.

Yep.

But in case of real acetaldehyde:  It was the first subject Drew covered in his great little off flavor series:

Has all the answers we don’t have here.

I detect low banana in Budweiser, which I have always wondered if comes from beechwood but I don’t really know.  But we digress.  Not acetaldehyde though, never thought it was that.

I and others seem to detect the green apple note resembling acetaldehyde in Michelob Ultra, which is why I don’t drink it.  But I guess it could be the ethyl hexanoate/ethyl caproate esters Rob mentioned contributing to that flavor note.

I mention this because I used Mich Ultra as a base beer for an off flavor presentation I did for one of the brew clubs I belong to.  About four people came up to me after the first session (I did it over several meetings) and asked me to use a different beer because of the green apple notes in the Mich Ultra.  I used Bud Light after that which I also don’t drink.

The was a guy who works for ABI that has said they don’t release beer unless it is below the threshold for acetaldehyde. He also said the Budweiser yeast produces appley esters. Mitch Steele said the same on his blog (now gone), and he worked for AB before Stone.

In a sensory training session, the acetaldehyde spike gave me the flavor of green jolly Roger candy, not apple.

We are trained that acetaldehyde=apple. We are not told there are esters=apple.

Point well taken, Jeff.  Thanks for the clarification.

Cool. Well my Kolsch has a green apply thing going on that will probably get dinged as acetaldehyde in the comp. I didn’t notice it last year’s entry but a judge commented on it even though it got a 2nd place. Due to that comment, I wanted to ensure that this batch didn’t have the same issue but this year it is a lot more noticeable to me.

Anyone get apple/citrus esters off of 2565?

WY2565 - used slurry less than one week old
59F for 72 hours
let rise to 64F
bump up to 70F at the end for a couple of days
crash to 30F for one week

Kolsch will definitely have apple and pear esters to my palate - and that is fine for the style.  I am a BJCP judge (only certified), but many competitions are corrupted by lager judges that don’t appreciate that lagers can have fruit esters without having acetaldehyde, especially in the lightest of the lagers and Kolsch beer styles.  It is a yeast driven thing many times (e.g., I get some lemon from 34/70 and liquid equivalents).  LODO brewing especially seems to bring out subtle flavor notes by locking them in (Helles with light honey and grape - but also with clean, refreshing maltiness that is considered a flaw by unknowing judges - I actually had a comment on a Helles in a competition that it was too richly malty, though it was a Weyermann pilsner malt and sauermalz only malt base beer).

Cheers!